Saft 16440 Emergency Light Replacement Battery 1.2V 2100mAh

Saft 16440 — 1.2V Ni-MH Replacement Battery

This is a 1.2V, 2100mAh Ni-MH cell for the Saft 16440 emergency lighting unit. It restores backup illumination function after the original cell has degraded past its discharge threshold. Dimensions are 43.70 x 20.10 x 17.14mm — confirm physical fit before installation.

• 16440 fitting compatibility: The 16440 unit uses a single Ni-MH cell on a continuous trickle-charge circuit. Voltage and cell format must match exactly — a cell outside spec will either refuse to charge or trigger a permanent fault LED on the controller board.
• Bench tested on actual hardware: We ran this cell through a full charge cycle and timed discharge load test. The BMS accepted charge within the standard float window, and cell voltage held above the cutoff threshold throughout the discharge curve.
• First-cycle conditioning after installation: Within 24 hours of fitting, hold the test button for the full rated duration. This confirms the cell accepts load and allows the charge controller to register capacity before your next scheduled compliance inspection.

Charge indicator staying red after new cell installation

A replacement cell that has been in storage will typically sit at a lower resting voltage than the charge controller expects at float. The controller reads this as a fault condition rather than a charging state, and holds the red LED. Most 16440 controllers need 12–24 hours of uninterrupted mains power before they accept the new cell voltage and switch to green. Do not pull the cell during this window — let the trickle circuit bring the voltage up gradually to approximately 1.4V per cell.

Emergency light dims or cuts out partway through a duration test

This happens when the cell has not completed a full conditioning charge before the test runs. A partially charged Ni-MH cell under load will show a sharp voltage drop earlier than rated capacity allows, triggering the fitting's low-voltage cutoff. The fix is straightforward: allow a full 24-hour charge after installation before running any test. If dimming still occurs after a full charge cycle, measure resting cell voltage — a healthy cell at full charge should read at or above 1.35V at rest.